The Jet was a Romanian Spectrum clone computer built in a telephone case! You can see the handset housing and the numeric keyboard replaced with black plastic masks.

The keyboard was made of printed pieces of paper inserted in transparent key-caps.

This system has been deeply modified by the user(s).

Zeno Mateescu, who owned a JET, reports:

The whole computer was more a HC-85 clone, designed more specificaly for computer games. That's where the name came from: JET-EM Aparat pentru jocuri pe ecran TV - machine for games on TV screen - if I remember well. It is indeed a Sinclair ZX Spectrum compatible computer. It didn't had any joystick connector (kempston or any other joystick) so I had to modify it to use a joystick. Another interesting thing about JET was that you
couldn't hear the program that was loading from the tape. On HC85, for example, you could hear that, let's call it noise, when loading the program.